Organic compound, light-emitting element, light-emitting device, display device, electronic device, and lighting device

Abstract

A novel organic compound that forms an exciplex emitting light with high efficiency is provided. An organic compound with a triarylamine skeleton in which the three aryl groups of the triarylamine skeleton are a p-biphenyl group, a fluoren-2-yl group, and a phenyl group to which a dibenzofuranyl group or a dibenzothiophenyl group is bonded. By the use of the organic compound and an organic compound with an electron-transport property, an exciplex that emits light with extremely high efficiency can be formed.

What is claimed is: 
     
       1. A host material for a light-emitting substance, the host material comprising:
 an organic compound represented by a formula (G1): 
 
       
         
           
           
               
               
           
         
         wherein:
 A represents one of a dibenzofuranyl group and a dibenzothiophenyl group; and 
 R 1  and R 2  each separately represents an alkyl group having 1 to 6 carbon atoms, and 
 
         wherein the host material is configured to provide excitation energy of the host material to the light-emitting substance. 
       
     
     
       2. The host material according to  claim 1 , wherein the organic compound is represented by a formula (G2): 
       
         
           
           
               
               
           
         
       
     
     
       3. The host material according to  claim 1 , wherein A represents one of groups represented by formulae (A-1) to (A-4): 
       
         
           
           
               
               
           
         
       
     
     
       4. The host material according to  claim 1 , wherein A represents a group represented by a formula (A-1) or (A-2): 
       
         
           
           
               
               
           
         
       
     
     
       5. The host material according to  claim 1 , wherein A represents a group represented by a formula (A-1): 
       
         
           
           
               
               
           
         
       
     
     
       6. The host material according to  claim 1 , wherein R 1  and R 2  each separately represent one of groups represented by formulae (R-1) to (R-12): 
       
         
           
           
               
               
           
         
       
     
     
       7. The host material according to  claim 1 , wherein both R 1  and R 2  are methyl groups. 
     
     
       8. The host material according to  claim 1 , wherein the organic compound is represented by a formula (100): 
       
         
           
           
               
               
           
         
       
     
     
       9. The host material according to  claim 1 , wherein the light-emitting substance is a phosphorescent substance. 
     
     
       10. The host material according to  claim 1 ,
 wherein the host material is a mixture comprising the organic compound and a first compound, and 
 wherein the first compound has an electron transport property. 
 
     
     
       11. The host material according to  claim 1 ,
 wherein the host material is a mixture comprising the organic compound and a first compound, and 
 wherein the first compound is a nitrogen-containing heteroaromatic compound. 
 
     
     
       12. A method for use of the host material according to  claim 1 , comprising the step of:
 co-evaporating the organic compound and the light-emitting substance. 
 
     
     
       13. A host material for a light-emitting substance, the host material comprising:
 an organic compound represented by a formula (G1): 
 
       
         
           
           
               
               
           
         
         wherein:
 A represents one of a dibenzofuranyl group and a dibenzothiophenyl group; 
 R 1  and R 2  each separately represent an alkyl group having 1 to 6 carbon atoms; and 
 the organic compound is capable of forming an exciplex with a nitrogen-containing heteroaromatic compound, and 
 
         wherein the exciplex is configured to provide excitation energy of the host material to the light-emitting substance. 
       
     
     
       14. The host material according to  claim 13 , wherein the organic compound is represented by a formula (G2): 
       
         
           
           
               
               
           
         
       
     
     
       15. The host material according to  claim 13 , wherein A represents one of groups represented by formulae (A-1) to (A-4): 
       
         
           
           
               
               
           
         
       
     
     
       16. The host material according to  claim 13 ,
 wherein the organic compound is capable to form an exciplex by a first compound, 
 wherein a HOMO level of the first compound is deeper than a HOMO level of the organic compound, and 
 wherein a LUMO level of the first compound is deeper than a LUMO level of the organic compound.